By this time it was clear that even France would soon be stricken to the heart unless Napoleon speedily concentrated his forces. On the north and east the allies were advancing with a speed that nonplussed the Emperor. Accustomed to sluggish movements on their part, he had not expected an invasion in force before the spring, and here it was in the first days of January. Bülow and Graham had overrun Holland. The allies, with the exception of the Czar, had no scruples about infringing the neutrality of Switzerland, as Napoleon had consistently done, and the constitution, which he had imposed upon that land eleven years before, now straightway collapsed. Detaching a strong corps southwards to hold the Simplon and Great St. Bernard Passes and threaten Lyons, Schwarzenberg led the allied Grand Army into France by way of Basel, Belfort, and Langres. The prompt seizure of the Plateau of Langres was an important success. The allies thereby turned the strong defensive lines of the Vosges Mountains, and of the Rivers Moselle and Meuse, so that Blücher, with his "Army of Silesia," was able rapidly to advance into Lorraine, and drive Victor from Nancy. Toul speedily surrendered, and the sturdy veteran then turned to the south-west, in order to come into touch with Schwarzenberg's columns. Neither leader delayed before the eastern fortresses. The allies had learnt from Napoleon to invest or observe them and press on, a course which their vast superiority of force rendered free from danger. Schwarzenberg, on the 25th, had 150,000 men between Langres, Chaumont, and Bar-sur-Aube; while Blücher, with about half those numbers, crossed the Marne at St. Dizier, and was drawing near to Brienne. In front of them were the weak and disheartened corps of Marmont, Ney, Victor, and Macdonald, mustering in all about 50,000 men. Desertions to the allies were frequent, and Blücher, wishing to show that the war was practically over, dismissed both deserters and prisoners to their homes.[401] But the war was far from over: it had not yet begun. Hitherto Napoleon had hurried on the preparations from Paris, but the urgency of the danger now beckoned him eastwards. As before, he left the Empress as Regent of France, but appointed King Joseph as Lieutenant-General of France. On Sunday, January 23rd, he held the last reception. It was in the large hall of the Tuileries, where the Parisian rabble had forced Louis XVI. to don the _bonnet rouge_. Another dynasty was now tottering to its fall; but none could have read its doom in the faces of the obsequious courtiers, or of the officers of the Parisian National Guards, who offered their homage to the heir of the Revolution.